1. Field of the Invention
The present invention relates generally to optical fiber handling systems, and more particularly to an optical fiber bend limiter that prevents optical fiber bending less than its minimum radius and unwanted contaminates from entering a optical fiber closure.
2. Description of the Related Art
Due to the fragile nature of optical fiber, there is a need to protect the fiber from external sources of stress, such as bending, pressure and strain, which can damage the fiber and/or cause degradation of the signal being transmitted via the fiber. For example, a fiber should not be bent sharply anywhere along its path. In addition to the possibility of breakage or fracture, if a fiber is bent past a critical angle, portions of transmitted light pulses will leak out, rather than being reflected within the fiber core, thereby attenuating the transmitted light pulses and degrading signal quality. Accordingly, it is necessary that a fiber be routed so that bends in the fiber are of a sufficient radius to substantially avoid occurrence of such light leakage.
The radius below which a fiber should not be bent to avoid light ray leakage is characterized as the minimum bend radius. Typically, the minimum bend radius varies with fiber design. However, in all fiber designs, bending the fiber to a radius smaller than its minimum bend radius may result in increased signal attenuation and/or a broken fiber.
In many fiber administration systems, as the optical fibers in a network enter the central office, they are directed into an optical distribution frame where the individual optical fibers are terminated in an organized manner. Such fiber administration systems are exemplified by the LGX® fiber administration system that is currently manufactured by Lucent Technologies of Murray Hill, N.J., the assignee herein.
As optical fiber distribution systems evolve there is a need to install, remove, and/or reroute optical fiber jumper cables used for making connections within or among shelves in a distribution frame. As the distribution system evolves more or less optical fibers may be connected within an optical closure. As such, an aperture for the insertion of optical fibers may not be in use. However, one of the concerns in the evolution of network distribution systems is the ability to keep unwanted contaminants from entering the fiber optic closure through an unused aperture.